A Polymeric Membrane Electrode Based on p-tert-butyl-thiacalix[4]arene Derivative for Thorium Determination

The aim of this study was to construct and characterize an ion selective electrode forthe potentiometric determination of thorium ions. on hand study we introduced a new calixarenemolecule p-tert-butyl-thiacalix[4]arene derivative as ionophore for thorium(iv) selectivepolymeric membrane electrode. due to the decisive role of solvent mediators, we fabricatedmembranes with the plasticizers dbp, dbbp, tep, oa, dop, 1-cn respectively and anionicadditive natpb. the best of the results were obtained with the membrane electrode compositionof dbp:pvc:ionophore:natpb (57%:35%:6%:2%). electrode sensor shows excellentdiscrimination towards th4+ ion in presence of other common cations. the resulting data clarifiedthat the electrode shows a nernstian slope of 14.9±0.6 mv per decade for th(iv) ions over abroad working concentration range of 8.0×10-8 to 1.0×10-1 mol/l. our electrode gives thepotential response in 7 sec for whole concentration range and this sensor can be used for sevenmonths. electrode has been successfully applied for many environmental and biological samplesof thorium (iv) and as an indicator in potentiometric titration.